Coupling



FIG. 1 is a front perspective view of a coupling.

FIG. 2 is a rear perspective view of the coupling of FIG. 1.

FIG. 3 is a right side view of the coupling of FIG. 1 with the left side view being a mirror image thereof.

FIG. 4 is a top plan view of the coupling of FIG. 1 with the bottom plan view being a mirror image thereof.

FIG. 5 is a front end view of the coupling of FIG. 1; and,

FIG. 6 is a top rear end view of the coupling of FIG. 1.

The broken lines in the drawings illustrate portions of the coupling and form no part of the claimed design. 

CLAIM The ornamental design for a coupling, as shown and described. 